Fomei Leader 8x56 DCF
| Magnification | Lens diameter | Angular field of view | Prisms | Eye relief | Weight | Price |
|---|---|---|---|---|---|---|
| 8 | 56 | 105/1000(6o) | BaK-4/roof | ? mm | 940 g | 499 PLN |
| Real front lens diameter |
Left: 55+/-
0.05 mm Right: 55+/- 0.05 mm |
3 / 8.0 pkt | ||||
|---|---|---|---|---|---|---|
| Real magnification | 8.11+/- 0.15x | 3/3.0 | ||||
| Transmission | 78.5+/- 1% | 9/25.0 | ||||
| Chromatic aberration | Excellent correction both in the field centre and at its edge. | 9.2/10.0 | ||||
| Astigmatism | Noticeable but still medium. | 5.9/10.0 | ||||
| Distortion | The distance of the first curved line from the field centre compared to the field of view radius: 41% +\- 3% | 4/10.0 | ||||
| Coma | It appears already near the centre of the field of view and is huge at the edge. | 4.9/10.0 | ||||
| Blurring at the edge of the FOV | The blur appears in the distance of 72% +\- 3% from the centre of the field of view. | 3.5/10.0 | ||||
| Darkening at the edge the FOV | Slight. | 3.8/5.0 | ||||
| Whiteness of the image | Cream image. | 3.3/5.0 | ||||
| Collimation | Exemplary. | 5/5.0 | ||||
| Internal reflections |
|
1.5/5.0 | ||||
| Housing | Small and handy. The veneer’s quality is good but you can feel it is slack on the inner tube and it doesn’t fit precisely. Regulated eyecups. Comfortable to look through. | 7.1/8.0 | ||||
| Focusing | Central screw is convenient, smooth and well-damped (full turn takes 730 degrees). Individual focusing with the usage of a joystick near the central screw. Joystick is a tad too short and might jam. Nothing moves outside. | 4.3/5.0 | ||||
| Tripod | Moderately convenient exit. | 2/3.0 | ||||
| Interpupilary distance | from 57.1 to 72.2mm | 3/6.0 | ||||
| Closest focusing distance | 2.80 m | 2/2.0 | ||||
| Eyepieces FOV | Eyepieces with the apparent field of view of 48.4 deg (according to simple formula) and 45.8 deg (according to tangent formula). | 3/20.0 | ||||
| Field of view | Measured by us it amounted to 5.97 degrees +\- 0.03 degree and it was in accordance with the specification in the margin of error. The field of view typical for this class of equipment. | 5/8.0 | ||||
| Quality of the interior of the barrels | Dark and gray inside but a bit shiny. Some specks of dust. A big scratch on the left prism. | 2.3/5.0 | ||||
| Vignetting |
Truncated pupils are the effect of too small prisms. |
4.5/8.0 | ||||
| Prisms quality | Good BaK-4. | 8/8.0 | ||||
| Antireflection coatings | Greenish on objective lenses, green-blue on eyepieces, no visible coatings on prisms. Medium intensity. | 3.5/5.0 | ||||
| Warranty [years] | 3 | 3/6.0 | ||||
| Final result | 54.6% | 103.8 / 190 pkt | ||||
| Econo result | 0pkt. |
Summary
Pros:
- quite solid barrel,
- excellent chromatic aberration correction,
- slight light fall-off at the edge of the field of view,
- exemplary collimation,
- good BaK-4 prisms,
- sharp image from 2.8 meters.
Cons:
- low transmission in the blue and green part of the spectrum,
- truncated exit pupils,
- very weak against bright light,
- image sharpness at the edge of the field of view should have been better,
- maximum IPD too narrow.
The final result certainly can’t bowl anybody over. If you thought, however, that a roof-prism set of binoculars with 8x56 parameters and the price tag of 150 Euro would achieve a fantastic result you either believe in miracles or you don’t believe in the laws of physics. Excellent anti-reflection coatings, big, high-quality prisms with an efficient reflection layer and phase correction inside a solid, nitrogen-filled and waterproof housing –these features in a night 8x56 class instrument are simply a must. You can’t have it all for 150 Euro and you shouldn’t kid yourself that it is somehow possible.
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What’s more, looking at the tested binoculars from the perspective of its price there is really nothing to criticize. After all, the score above 100 points is not bad – in our tests we consider it to be a medium level. We get what we’ve paid for. The binoculars don’t look shoddy - it won’t fall apart after a year of usage, a prism won’t come off if the instrument falls down on a table (such things do happen in the case of the cheapest devices). The Leader 8x56 has an excellent chromatic aberration correction level, its prisms are of high quality and its edge brightness loss is very slight. In all different test categories it achieved average or a bit lower than average results and evident slip-ups are just few. We can count among them weak work against bright light, low transmission in the blue and green part of the visible spectrum and truncated pupils.
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